Rated 5 out of 5 stars

But can it works with RSS-accounts?

Đánh giá này là cho một phiên bản trước của tiện ích (0.9.1). 

Archiving of RSS accounts is not possible in Thunderbird. Therefore the addon can't do it.

Maybe you can create a Filter which moves the RSS messages to a folder inside a POP3 account. Then you can archive this one. Sounds a bit tricky but may work.